Community-acquired pneumonia in elderly patients

Pulmonary Diseases in Older Patients: Understanding and Addressing the Challenges

As the global population ages, pulmonary diseases among older people have emerged as a significant and growing public health concern. The increasing incidence of these conditions has led to higher rates of morbidity and mortality among older adults. This perspective study offers a thorough overview of the prevalent pulmonary diseases affecting the elderly demographic. It delves into the challenges encountered during the diagnosis and management of these conditions in older individuals, considering factors such as comorbidities, functional limitations, and medication complexities. Furthermore, innovative strategies and personalized interventions such as precision medicine, advanced therapies, telemedicine solutions, and patient-centered support systems aimed at enhancing the care provided to older individuals grappling with pulmonary disorders are thoroughly explored. By addressing the unique needs and complexities of this vulnerable population, healthcare systems can strive towards improving outcomes and enhancing the quality of life for elderly individuals affected by pulmonary diseases.

Outcomes of Multimodal Treatment in Elderly Patients with Localized Non-Small Lung Cancer from a Radiation Oncology Point of View: Special Focus on Low-Dose Cisplatin

Identification of the optimal treatment strategy is challenging in elderly with localized non-small cell lung cancer (NSCLC). Concurrent chemotherapy with low-dose cisplatin represents an option for elderly. Outcomes (1) in elderly (≥70 years, n = 158) vs. younger patients (n = 188) and (2), independently of age, in definitive radiochemotherapy, with low-dose cisplatin (n = 125) vs. cisplatin/vinorelbine (n = 76) were studied. Elderly included more males, had a lower Karnofsky index, more comorbidities, and lower stages. Low-dose cisplatin patients (vs. cisplatin/vinorelbine) had higher age, more comorbidities, and lower stages. We observed reduced dermatitis and dysphagia and increased anemia and thrombocytopenia in elderly vs. younger patients, without increased ≥grade 3 toxicities. Low-dose cisplatin was less toxic than cisplatin/vinorelbine. Survival outcomes were lower in elderly vs. younger and comparable between low-dose cisplatin and cisplatin/vinorelbine. In elderly, gender, Karnofsky index, stage, and multimodal treatment (including additional surgery/systemic therapy) were identified as prognostic factors. In conclusion, we found evidence for an acceptable toxicity profile and the need for improvement of outcomes in elderly with localized NSCLC. Multimodal strategies (including additional surgery/systemic treatment) showed favorable outcomes and should be reasonably considered in elderly who are deemed fit enough. Low-dose cisplatin should be discussed on an individual basis due to favorable toxicity and outcomes.

Serum Interleukin-6 and Serum Ferritin Levels Are the Independent Risk Factors for Pneumonia in Elderly Patients

Pneumonia is a common infection in elderly patients. We explored the correlations of serum interleukin-6 (IL-6) and serum ferritin (SF) levels with immune function/disease severity in elderly pneumonia patients. Subjects were allocated into the mild pneumonia (MP), severe pneumonia (SP), and normal groups, with their age/sex/body mass index/ disease course and severity/blood pressure/comorbidities/medications/prealbumin (PA)/albumin (ALB)/C-reactive protein (CRP)/procalcitonin (PCT)/smoking status documented. The disease severity was evaluated by pneumonia severity index (PSI). T helper 17 (Th17)/regulatory T (Treg) cell ratios and IL-6/SF/immunoglobulin G (IgG)/Th17 cytokine (IL-21)/Treg cytokine (IL-10)/PA/ALB levels were assessed. The correlations between these indexes/independent risk factors in elderly patients with severe pneumonia were evaluated. There were differences in smoking and CRP/PCT/ALB/PA levels among the three groups, but only CRP/ALB were different between the MP/SP groups. Pneumonia patients exhibited up-regulated Th17 cell ratio and serum IL-6/SF/IL-21/IL-10/IgG levels, down-regulated Treg cell ratio, and greater differences were noted in severe cases. Serum IL-6/SF levels were positively correlated with disease severity, immune function, and IL-21/IL-10/IgG levels. Collectively, serum IL-6 and SF levels in elderly pneumonia patients were conspicuously positively correlated with disease severity and IL-21/IL-10/IgG levels. CRP, ALB, IL-6 and SF levels were independent risk factors for severe pneumonia in elderly patients.

Clinical factors associated with in-hospital mortality in elderly versus non-elderly pneumonia patients in the emergency department

BACKGROUND

Pneumonia is a respiratory infection with an increasing incidence with age. However, limited evidence has identified factors associated with its outcome among different age groups, especially in the elderly and in the emergency department (ED) setting. We aimed to identify clinical factors associated with in-hospital mortality in elderly versus non-elderly pneumonia patients in the ED.

METHODS

A retrospective observational study was conducted at the ED of Siriraj Hospital, Thailand. Patients aged at least 18 years old diagnosed with non-COVID pneumonia between June 1, 2021, and May 31, 2022, were included. They were categorized into the elderly (age ≥ 65 years) and non-elderly (age < 65 years) groups. The primary outcome was in-hospital mortality. We employed multivariate logistic regression models to identify independent factors associated with the outcome in each age group.

RESULTS

We enrolled 735 patients, 515 elderly and 222 non-elderly. There was no difference in in-hospital mortality rate between the two groups (39.0% in the elderly and 32.9% in the non-elderly; p = 0.116). In the elderly cohort, independent factors associated with in-hospital mortality were do-not-resuscitate (DNR) status (adjusted odds ratio (aOR) 12.89; 95% confidence interval (CI) 7.19-23.1; p < 0.001), Glasgow Coma Scale (GCS) score (aOR 0.91; 95%CI 0.85-0.96; p = 0.002), hemoglobin level (aOR 0.9; 95%CI 0.82-0.98; p = 0.012) and the type of initial oxygen support (p = 0.05). Among non-elderly patients, independent factors were DNR status (aOR 6.81; 95%CI 3.18-14.59; p < 0.001), GCS score (aOR 0.89; 95%CI 0.8-0.99; p = 0.025), platelet level (aOR 1; 95%CI 1-1; p = 0.038), Charlson Comorbidity Index (CCI) (aOR 1.12; 95%CI 0.99-1.28; p = 0.078), and the type of initial oxygen support p = 0.079).

CONCLUSION

In pneumonia patients presenting to the ED, DNR status, lower GCS score, and more invasive initial oxygen supplementation were independently associated with in-hospital mortality in both elderly and non-elderly groups. However, lower hemoglobin level was only associated with in-hospital mortality in the elderly, while higher CCI and lower platelet count were independent factors only in the non-elderly. These findings emphasize the importance of age-specific considerations for the disease, and these factors are potential prognostic markers that may be used in clinical practice to improve patient outcomes.

Improving Early Recognition of Coccidioidomycosis in Urgent Care Clinics: Analysis of an Implemented Education Program

Background

Only 0.2% of coccidioidomycosis (CM) diagnoses were made in patients (pts) with pneumonia (PNA) in urgent care (UC), because they were not being tested for CM. Our objective in this study was to improve CM testing rates.

Methods

This was a time series of clinician practice before and after an intervention that occurred at UC clinics in Phoenix and Tucson Arizona. All patients in UC were >18 years old. We included information about CM in periodic educational activities for clinicians. Coccidioidal serologic testing (CST), CST results, and their relation to International Classification of Diseases, Tenth Revision (ICD-10) codes were extracted from medical records.

Results

Urgent care received 2.1 million visits from 1.5 million patients. The CST orders per 10⁴ visits increased from 5.5 to 19.8 (P < .0001). Percentage positive CSTs were highest for August, November, and December (17.0%) versus other months (10.6%). Positive CSTs were associated with PNA ICD-10 codes, and, independently, for Erythema nodosum (EN) which had the highest positivity rate (61.4%). Testing of PNA pts increased on first visits and on second visits when the first CST was negative. Yearly rates of PNA due to CM ranged from 17.3% to 26.0%. Despite this improvement, CST was still not done for over three quarters of pts with PNA. This was a noncomparative study.

Conclusions

Routine quality improvement activities have significantly but only partially improved rates of testing pts with PNA for CM in UC clinics located in a highly endemic area. Innovative strategies may be needed to improve current practice. Also in our region, EN, independent of PNA, is a strong predictor of CM.

Biomarkers as point-of-care tests to guide prescription of antibiotics in people with acute respiratory infections in primary care

BACKGROUND

Acute respiratory infections (ARIs) are by far the most common reason for prescribing an antibiotic in primary care, even though the majority of ARIs are of viral or non-severe bacterial aetiology. It follows that in many cases antibiotic use will not be beneficial to a patient's recovery but may expose them to potential side effects. Furthermore, limiting unnecessary antibiotic use is a key factor in controlling antibiotic resistance. One strategy to reduce antibiotic use in primary care is point-of-care biomarkers. A point-of-care biomarker (test) of inflammation identifies part of the acute phase response to tissue injury regardless of the aetiology (infection, trauma, or inflammation) and may be used as a surrogate marker of infection, potentially assisting the physician in the clinical decision whether to use an antibiotic to treat ARIs. Biomarkers may guide antibiotic prescription by ruling out a serious bacterial infection and help identify patients in whom no benefit from antibiotic treatment can be anticipated. This is an update of a Cochrane Review first published in 2014.

OBJECTIVES

To assess the benefits and harms of point-of-care biomarker tests of inflammation to guide antibiotic treatment in people presenting with symptoms of acute respiratory infections in primary care settings regardless of patient age.

SEARCH METHODS

We searched CENTRAL (2022, Issue 6), MEDLINE (1946 to 14 June 2022), Embase (1974 to 14 June 2022), CINAHL (1981 to 14 June 2022), Web of Science (1955 to 14 June 2022), and LILACS (1982 to 14 June 2022). We also searched three trial registries (10 December 2021) for completed and ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in primary care patients with ARIs that compared the use of point-of-care biomarkers with standard care. We included trials that randomised individual participants, as well as trials that randomised clusters of patients (cluster-RCTs).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data on the following primary outcomes: number of participants given an antibiotic prescription at index consultation and within 28 days follow-up; participant recovery within seven days follow-up; and total mortality within 28 days follow-up. We assessed risk of bias using the Cochrane risk of bias tool and the certainty of the evidence using GRADE. We used random-effects meta-analyses when feasible. We further analysed results with considerable heterogeneity in prespecified subgroups of individual and cluster-RCTs.

MAIN RESULTS

We included seven new trials in this update, for a total of 13 included trials. Twelve trials (10,218 participants in total, 2335 of which were children) evaluated a C-reactive protein point-of-care test, and one trial (317 adult participants) evaluated a procalcitonin point-of-care test. The studies were conducted in Europe, Russia, and Asia. Overall, the included trials had a low or unclear risk of bias. However all studies were open-labelled, thereby introducing high risk of bias due to lack of blinding. The use of C-reactive protein point-of-care tests to guide antibiotic prescription likely reduces the number of participants given an antibiotic prescription, from 516 prescriptions of antibiotics per 1000 participants in the control group to 397 prescriptions of antibiotics per 1000 participants in the intervention group (risk ratio (RR) 0.77, 95% confidence interval (CI) 0.69 to 0.86; 12 trials, 10,218 participants; I² = 79%; moderate-certainty evidence).  Overall, use of C-reactive protein tests also reduce the number of participants given an antibiotic prescription within 28 days follow-up (664 prescriptions of antibiotics per 1000 participants in the control group versus 538 prescriptions of antibiotics per 1000 participants in the intervention group) (RR 0.81, 95% CI 0.76 to 0.86; 7 trials, 5091 participants; I² = 29; high-certainty evidence). The prescription of antibiotics as guided by C-reactive protein tests likely does not reduce the number of participants recovered, within seven or 28 days follow-up (567 participants recovered within seven days follow-up per 1000 participants in the control group versus 584 participants recovered within seven days follow-up per 1000 participants in the intervention group) (recovery within seven days follow-up: RR 1.03, 95% CI 0.96 to 1.12; I² = 0%; moderate-certainty evidence) (recovery within 28 days follow-up: RR 1.02, 95% CI 0.79 to 1.32; I² = 0%; moderate-certainty evidence). The use of C-reactive protein tests may not increase total mortality within 28 days follow-up, from 1 death per 1000 participants in the control group to 0 deaths per 1000 participants in the intervention group (RR 0.53, 95% CI 0.10 to 2.92; I² = 0%; low-certainty evidence). We are uncertain as to whether procalcitonin affects any of the primary or secondary outcomes because there were few participants, thereby limiting the certainty of evidence. We assessed the certainty of the evidence as moderate to high according to GRADE for the primary outcomes for C-reactive protein test, except for mortality, as there were very few deaths, thereby limiting the certainty of the evidence.

AUTHORS' CONCLUSIONS

The use of C-reactive protein point-of-care tests as an adjunct to standard care likely reduces the number of participants given an antibiotic prescription in primary care patients who present with symptoms of acute respiratory infection. The use of C-reactive protein point-of-care tests likely does not affect recovery rates. It is unlikely that further research will substantially change our conclusion regarding the reduction in number of participants given an antibiotic prescription, although the size of the estimated effect may change.  The use of C-reactive protein point-of-care tests may not increase mortality within 28 days follow-up, but there were very few events. Studies that recorded deaths and hospital admissions were performed in children from low- and middle-income countries and older adults with comorbidities.  Future studies should focus on children, immunocompromised individuals, and people aged 80 years and above with comorbidities. More studies evaluating procalcitonin and potential new biomarkers as point-of-care tests used in primary care to guide antibiotic prescription are needed.  Furthermore, studies are needed to validate C-reactive protein decision algorithms, with a specific focus on potential age group differences.

Predictors of Vancomycin-Resistant Enterococcus spp. Intestinal Carriage among High-Risk Patients in University Hospitals in Serbia

The predictors of intestinal carriage of vancomycin-resistant Enterococcus spp. (VRE) among high-risk patients in the counties of the Southeast Europe Region are insufficiently investigated, yet they could be of key importance in infection control. The aim of the study was to identify risk factors associated with fecal VRE colonization among high-risk inpatients in university hospitals in Serbia. The study comprised 268 inpatients from three university hospitals. Data on patient demographics and clinical characteristics, length of hospital stay, therapy, and procedures were obtained from medical records. Chi-squared tests and univariate and multivariate logistic regressions were performed. Compared to the hemodialysis departments, stay in the geriatric departments, ICUs, and haemato-oncology departments increased the risk for VRE colonization 7.6, 5.4, and 5.5 times, respectively. Compared to inpatients who were hospitalized 48 h before stool sampling for VRE isolation, inpatients hospitalized 3–7, 8–15, and longer than 16 days before sampling had 5.0-, 4.7-, and 6.6-fold higher risk for VRE colonization, respectively. The use of cephalosporins and fluoroquinolones increased the risk for VRE colonization by 2.2 and 1.9 times, respectively. The age ≥ 65 years increased the risk for VRE colonization 2.3 times. In comparison to the University Clinical Centre of Serbia, the hospital stays at Zemun and Zvezdara University Medical Centres were identified as a protector factors. The obtained results could be valuable in predicting the fecal VRE colonization status at patient admission and consequent implementation of infection control measures targeting at-risk inpatients where VRE screening is not routinely performed.

Change for the Better: Severe Pneumonia at the Emergency Department

This is a single-centre observational study of adult patients with severe pneumonia requiring hospitalization conducted at the emergency department. During the observation period (94 weeks), 398 patients were diagnosed with severe pneumonia and required further treatment at the hospital. The median age of patients was 73 years. About 65% of patients had at least one chronic comorbidity. Almost 30% of patients had cardiovascular disorders, and 13% had diabetes mellitus. The average Emergency Department length of stay was 3.56 days. The average length of hospitalization was 15.8 days. Overall, 94% of patients treated for pneumonia received a beta-lactam antibiotic. The median time from ED admission to the administration of the first dose of antimicrobial agent was less than 6 h. Microbiology test samples were obtained from 48.7% patients. Gram-positive cocci were isolated most commonly (52.9%) from blood samples. Biological material from the lower respiratory tract was collected from 8.3% of patients, and from 47.2% of positive samples, fungi were cultured. The urine samples were obtained from 35.9% patients, and Gram-negative rods (76%) were isolated most commonly. Overall, 16.1% of patients died during the hospitalization. The mean age of patients who died was 79 years. This observational study is the first single-centre study conducted as part of the Polish Emergency Department Research Organization (PEDRO) project. It aims to provide up-to-date information about patients with pneumonia in order to improve medical care and develop local diagnostic and therapeutic recommendations.

Functional, transcriptional, and microbial shifts associated with healthy pulmonary aging in rhesus macaques

Older individuals are at increased risk of developing severe respiratory infections. However, our understanding of the impact of aging on the respiratory tract remains limited as samples from healthy humans are challenging to obtain and results can be confounded by variables such as smoking and diet. Here, we carry out a comprehensive cross-sectional study (n = 34 adult, n = 49 aged) to define the consequences of aging on the lung using the rhesus macaque model. Pulmonary function testing establishes similar age and sex differences as humans. Additionally, we report increased abundance of alveolar and infiltrating macrophages and a concomitant decrease in T cells were in aged animals. scRNAseq reveals shifts from GRZMB to IFN expressing CD8⁺ T cells in the lungs. These data provide insight into age-related changes in the lungs’ functional, microbial, and immunological landscape that explain increased prevalence and severity of respiratory diseases in the elderly.

Rhoades et al. describe age-associated functional, microbial, and immunological changes in the lung using the rhesus macaque model. These data will support further studies aimed at designing and testing interventions to mitigate the impact of age-associated shifts in the lung environment to reduce age-related pulmonary disease in the elderly.

Age-Related Intestinal Dysbiosis and Enrichment of Gut-specific Bacteria in the Lung Are Associated With Increased Susceptibility to Streptococcus pneumoniae Infection in Mice

The portion of the global population that is over the age of 65 is growing rapidly and this presents a number of clinical complications, as the aged population is at higher risk for various diseases, including infection. For example, advanced age is a risk factor for heightened morbidity and mortality following infection with Streptococcus pneumoniae. This increased vulnerability is due, at least in part, to age-related dysregulation of the immune response, a phenomenon termed immunosenescence. However, our understanding of the mechanisms influencing the immunosenescent state and its effects on the innate immune response to pneumonia remain incomplete. Recently, a role for the gut microbiome in age-specific alterations in immunity has been described. Here, we utilized a murine model of intranasal Streptococcus pneumoniae infection to investigate the effects of age on both the innate immune response and the intestinal microbial populations after infection. In aged mice, compared to their younger counterparts, infection with Streptococcus pneumoniae led to increased mortality, impaired lung function and inadequate bacterial control. This poor response to infection was associated with increased influx of neutrophils into the lungs of aged mice 24 h after infection. The exacerbated pulmonary immune response was not associated with increased pro-inflammatory cytokines in the lung compared to young mice but instead heightened expression of immune cell recruiting chemokines by lung neutrophils. Bacterial 16S-rRNA gene sequencing of the fecal microbiome of aged and young-infected mice revealed expansion of Enterobacteriaceae in the feces of aged, but not young mice, after infection. We also saw elevated levels of gut-derived bacteria in the lung of aged-infected mice, including the potentially pathogenic symbiote Escherichia coli. Taken together, these results reveal that, when compared to young mice, Streptococcus pneumoniae infection in age leads to increased lung neutrophilia along with potentially pathogenic alterations in commensal bacteria and highlight potential mechanistic targets contributing to the increased morbidity and mortality observed in infections in age.

Cost impact analysis of novel host-response diagnostic for patients with community-acquired pneumonia in the emergency department

BACKGROUND

There is significant over-prescription of antibiotics for suspected community-acquired pneumonia (CAP) patients as bacterial and viral pathogens are difficult to differentiate. To address this issue, a host response diagnostic called MeMed BV (MMBV) was developed that accurately differentiates bacterial from viral infection at the point of need by integrating measurements of multiple biomarkers. A literature-based cost-impact model was developed that compared the cost impact and clinical benefits between using the standard of care diagnostics combined with MMBV relative to standard of care diagnostics alone.

METHODS

The patient population was stratified according to the pneumonia severity index, and cost savings were considered from payer and provider perspectives. Four scenarios were considered. The main analysis considers the cost impact of differences in antibiotic stewardship and resulting adverse events. The first, second, and third scenarios combine the impacts on antibiotic stewardship with changes in hospital admission probability, length of hospital stay and diagnosis related group (DRG) reallocation, and hospital admission probability, length of stay, and DRG reallocation in combination, respectively.

RESULTS

The main analysis results show overall per-patient savings of $37 for payers and $223 for providers. Scenarios 1, 2, and 3 produced savings of $137, $189, and $293 for payers, and $339, $713, and $809 for providers, respectively.

LIMITATIONS

Models are simulations of real-world clinical processes, and are not sensitive to variations in clinical practice driven by differences in physician practice styles, differences in facility-level practice patterns, and patient comorbidities expected to exacerbate the clinical impact of CAP. Hospital models are limited to costs and do not consider differences in revenue associated with each approach.

CONCLUSIONS

Introducing MMBV to the current SOC diagnostic process is likely to be cost-saving to both hospitals and payers when considering impacts on antibiotic distribution, hospital admission rate, hospital LOS, and DRG reallocation.

Bacterial effluxome as a barrier against antimicrobial agents: structural biology aspects and drug targeting

Antimicrobial resistance (AMR) is fast becoming a medical crisis affecting the entire global population. The bacterial membrane is the first layer of defense for the bacteria against antimicrobial agents (AMA), specifically transporters in the membrane efflux these AMA out of the bacteria and plays a significant role in the AMR development. Understanding the structure and the functions of these efflux transporters is essential to overcome AMR. This review discusses efflux transporters (primary, secondary, and tripartite), their domain architectures, substrate specificities, and efflux pump inhibitors (EPI). Special emphasis on nosocomial ESKAPEE (Enterococcus faecium., Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp. and Escherichia coli) pathogens, their multidrug efflux targets and inhibitors are discussed. Deep knowledge about the functioning of efflux pumps and their structural aspects will open up opportunities for developing new EPI, which could be used along with AMA as combination therapy to overcome the emerging AMR crisis.

The Adjuvanted Recombinant Zoster Vaccine Co-Administered with the 13-valent Pneumococcal Conjugate Vaccine in Adults Aged ≥50 Years: a Randomized Trial

BACKGROUND

Herpes zoster (HZ) results from reactivation of latent varicella-zoster virus. Adults at increased risk of HZ (due to immunocompromising conditions or older age) are also at risk of pneumococcal disease, both of which are preventable by vaccination. We evaluated simultaneous versus sequential administration of the adjuvanted recombinant zoster vaccine (RZV) and the 13-valent pneumococcal conjugate vaccine (PCV13) in adults aged ≥50 years.

METHODS

In this phase IIIB multinational trial (NCT03439657), participants were randomized 1:1 to receive either the first RZV dose and PCV13 simultaneously followed by the second RZV dose two months later (Co-Ad, N=449), or at two-month intervals, PCV13, the first RZV dose, and the second RZV dose sequentially (Control, N=463). Objectives were to demonstrate that immune responses to both vaccines are non-inferior when co-administered compared to sequential administration and to evaluate the safety of their co-administration.

RESULTS

The RZV vaccine response rate (VRR) in the Co-Ad group was 99.1% (95% confidence interval [CI]: 97.6-99.7), meeting the VRR success criterion. Non-inferiority criteria for the Co-Ad versus Control group were also met for anti-glycoprotein E antibodies (adjusted geometric mean concentration Control/Co-Ad ratio 1.07 [95%CI: 0.99-1.16]) and all PCV13 serotypes (adjusted antibody geometric mean titer Control/Co-Ad ratios 1.02 [95%CI: 0.86-1.22] to 1.36 [95%CI: 1.07-1.73]). Upon co-administration, the frequency of solicited local adverse events was consistent with the known safety profile of each individual vaccine, whereas solicited general adverse events were within the same range as for RZV alone.

CONCLUSIONS

RZV co-administered with PCV13 had an acceptable safety profile. Humoral immune responses to both vaccines were non-inferior when co-administered compared to sequential administration. These results suggest that adults may benefit from receiving RZV and a PCV at the same healthcare visit.

The effects of aging on host resistance and disease tolerance to SARS-CoV-2 infection

The ongoing coronavirus disease 2019 (COVID-19) crisis caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a large-scale pandemic that is afflicting millions of individuals in over 200 countries. The clinical spectrum caused by SARS-CoV-2 infections can range from asymptomatic infection to mild undifferentiated febrile illness to severe respiratory disease with multiple complications. Elderly patients (aged 60 and above) with comorbidities such as cardiovascular diseases and diabetes mellitus appear to be at highest risk of a severe disease outcome. To protect against pulmonary immunopathology caused by SARS-CoV-2 infection, the host primarily depends on two distinct defense strategies: resistance and disease tolerance. Resistance is the ability of the host to suppress and eliminate incoming viruses. By contrast, disease tolerance refers to host responses that promote host health regardless of their impact on viral replication. Disruption of either resistance or disease tolerance mechanisms or both could underpin predisposition to elevated risk of severe disease during viral infection. Aging can disrupt host resistance and disease tolerance by compromising immune functions, weakening of the unfolded protein response, progressive mitochondrial dysfunction, and altering metabolic processes. A comprehensive understanding of the molecular mechanisms underlying declining host defense in elderly individuals could thus pave the way to provide new opportunities and approaches for the treatment of severe COVID-19.

Distribution of Pathogens in Elderly Chinese Patients With Pneumonia: A Systematic Review and Meta-Analysis

Background: To summarize the distribution of pathogenic bacteria in elderly Chinese patients with pneumonia and provide guidance for the clinical application of antibiotics. Methods: The electronic databases of PubMed, Embase, Cochrane library, and China National Knowledge Infrastructure were searched. The primary outcomes included the prevalence of gram-positive cocci, gram-negative bacilli, and fungus. The summary prevalence and 95% confidence interval (CI) were calculated using the random-effects model. Results: A total of 17 retrospective studies reporting a total of 5,729 elderly patients with pneumonia were selected for final analysis. The summary prevalence of gram-positive cocci was 25% (95% CI: 20-30%; p < 0.001), whereas the prevalence of gram-negative bacilli was 56% (95% CI: 46-67%; p < 0.001). Moreover, the pooled prevalence of fungus in elderly patients with pneumonia was 11% (95% CI: 8-14%; p < 0.001). The most common gram-positive cocci were Staphylococcus aureus (ES: 8%; 95% CI: 6-11%; p <0.001), Streptococcus hemolyticus (ES: 7%; 95% CI: 6-8%; p < 0.001), and Streptococcus pneumoniae (ES: 5%; 95% CI: 3-7%; p < 0.001). Pseudomonas aeruginosa (ES: 18%; 95% CI: 14-22%; p <0.001) and Klebsiella pneumoniae (ES: 14%; 95% CI: 11-18%; p <0.001) were most common gram-negative bacilli. Furthermore, the pooled prevalence of Candida albicans in elderly patients with pneumonia was 6% (95% CI: 5-8%; p < 0.001). Conclusions: The findings demonstrated the comprehensive distribution of pathogenic bacteria in elderly Chinese patients with pneumonia, which could guide further antibiotic therapies.

Intranasal Vaccine Delivery Technology for Respiratory Tract Disease Application with a Special Emphasis on Pneumococcal Disease

This mini-review will cover recent trends in intranasal (IN) vaccine delivery as it relates to applications for respiratory tract diseases. The logic and rationale for IN vaccine delivery will be compared to methods and applications accompanying this particular administration route. In addition, we will focus extended discussion on the potential role of IN vaccination in the context of respiratory tract diseases, with a special emphasis on pneumococcal disease. Here, elements of this disease, including its prevalence and impact upon the elderly population, will be viewed from the standpoint of improving health outcomes through vaccine design and delivery technology and how IN administration can play a role in such efforts.

Insights Into the Effects of Mucosal Epithelial and Innate Immune Dysfunction in Older People on Host Interactions With Streptococcus pneumoniae

In humans, nasopharyngeal carriage of Streptococcus pneumoniae is common and although primarily asymptomatic, is a pre-requisite for pneumonia and invasive pneumococcal disease (IPD). Together, these kill over 500,000 people over the age of 70 years worldwide every year. Pneumococcal conjugate vaccines have been largely successful in reducing IPD in young children and have had considerable indirect impact in protection of older people in industrialized country settings (herd immunity). However, serotype replacement continues to threaten vulnerable populations, particularly older people in whom direct vaccine efficacy is reduced. The early control of pneumococcal colonization at the mucosal surface is mediated through a complex array of epithelial and innate immune cell interactions. Older people often display a state of chronic inflammation, which is associated with an increased mortality risk and has been termed 'Inflammageing'. In this review, we discuss the contribution of an altered microbiome, the impact of inflammageing on human epithelial and innate immunity to S. pneumoniae, and how the resulting dysregulation may affect the outcome of pneumococcal infection in older individuals. We describe the impact of the pneumococcal vaccine and highlight potential research approaches which may improve our understanding of respiratory mucosal immunity during pneumococcal colonization in older individuals.

Understanding the Impact of Pneumonia and Other Complications in Elderly Liver Transplant Recipients: An Analysis of NSQIP Transplant

Despite an increasing demand for liver transplantation in older patients, our understanding of posttransplant outcomes in older recipients is limited to basic recipient and graft survival. Using National Surgical Quality Improvement Program Transplant, we tracked early outcomes after liver transplantation for patients >65.

Methods

We conducted a retrospective analysis of patients in National Surgical Quality Improvement Program Transplant between March 1, 2017 and March 31, 2019. Recipients were followed for 1 y after transplant with follow-up at 30, 90, and 365 d. Data were prospectively gathered using standard definitions across all sites.

Results

One thousand seven hundred thirty-one adult liver transplants were enrolled; 387 (22.4%) were >65 y old. The majority of older recipients were transplanted for hepatocellular carcinoma. The older cohort had a lower lab Model for End-Stage Liver Disease and was less likely to be hospitalized at time of transplant. Overall, older recipients had higher rates of pneumonia but no difference in intensive care unit length of stay (LOS), total LOS, surgical site infection, or 30-d readmission. Subgroup analysis of patients with poor functional status revealed a significant difference in intensive care unit and total LOS. Pneumonia was even more common in older patients and had a significant impact on overall survival.

Conclusions

By targeting patients with hepatocellular carcinoma and lower Model for End-Stage Liver Diseases, transplant centers can achieve nearly equivalent outcomes in older recipients. However, older recipients with poor functional status require greater resources and are more likely to develop pneumonia. Pneumonia was strongly associated with posttransplant survival and represents an opportunity for improvement. By truly understanding the outcomes of elderly and frail recipients, transplant centers can improve outcomes for these higher-risk recipients.

Incidence, risk factors, and viral etiology of community-acquired acute lower respiratory tract infection among older adults in rural north India

BACKGROUND

There are limited data on incidence, risk factors and etiology of acute lower respiratory tract infection (LRTI) among older adults in low- and middle-income countries.

METHODS

We established a cohort of community dwelling older adults ≥60 years and conducted weekly follow-up for acute respiratory infections (ARI) during 2015-2017. Nurses assessed ARI cases for LRTI, collecting combined nasal/throat swabs from all LRTI cases and an equal number of age- and sex-matched asymptomatic neighbourhood controls. Swabs were tested for influenza viruses, respiratory syncytial virus (RSV), human metapneumovirus (hMPV), and parainfluenza viruses (PIV) using polymerase chain reaction. LRTI and virus-specific LRTI incidence was calculated per 1000 person-years. We estimated adjusted incidence rate ratios (IRR) for risk factors using Poisson regression and calculated etiologic fractions (EF) using adjusted odds ratios for detection of viral pathogens in LRTI cases vs controls.

RESULTS

We followed 1403 older adults for 2441 person-years. LRTI and LRTI-associated hospitalization incidences were 248.3 (95% confidence interval (CI) = 229.3-268.8) and 12.7 (95% CI = 8.9-18.1) per 1000 person-years. Persons with pre-existing chronic bronchitis as compared to those without (incidence rate ratio (IRR) = 4.7, 95% CI = 3.9-5.6); aged 65-74 years (IRR = 1.6, 95% CI = 1.3-2.0) and ≥75 years (IRR = 1.8, 95% CI = 1.4-2.4) as compared to 60-64 years; and persons in poorest wealth quintile (IRR = 1.4, 95% CI = 1.1-1.8); as compared to those in wealthiest quintile were at higher risk for LRTI. Virus was detected in 10.1% of LRTI cases, most commonly influenza (3.8%) and RSV (3.0%). EF for RSV and influenza virus was 83.9% and 83.6%, respectively.

CONCLUSION

In this rural cohort of older adults, the incidence of LRTI was substantial. Chronic bronchitis was an important risk factor; influenza virus and RSV were major viral pathogens.

Clinical Benefits and Cost-Effectiveness of Moxifloxacin as Initial Treatment for Community-Acquired Pneumonia: A Meta-Analysis and Economic Evaluation

PURPOSE

Moxifloxacin and levofloxacin are currently recommended as empirical initial treatment options for community-acquired pneumonia (CAP) in China according to guidelines. Most studies that evaluated the efficacy and safety of moxifloxacin and levofloxacin in treating CAP as initial empirical treatment were single-centered trials assessing different clinical end points. In addition, there is limited research investigating moxifloxacin's clinical benefits in the context of health care resource utilization and reimbursement from the payer's perspective in China. Hence, this study was aimed at comparing the clinical efficacy of moxifloxacin and levofloxacin by conducting a meta-analysis and assessing their economic value from the China payer's perspective through a cost-utility analysis model.

METHODS

For the meta-analysis, 6 bibliographic databases were searched for relevant publications from January 2000 to August 2020, and studies were assessed for eligibility under predetermined criteria. Meta-analysis was performed by using a random effects model when analyses included >2 trials. For the economic evaluation, a decision-tree model was constructed to investigate the cost-utility of moxifloxacin versus levofloxacin as initial regimens in the treatment of CAP inpatients. Parameter values were derived from meta-analysis, published literature, and clinician survey. The outcome was reported in the form of an incremental cost-effectiveness ratio. One-way sensitivity analysis and probabilistic sensitivity analysis were undertaken to assess the robustness of the model.

FINDINGS

Twenty-seven randomized controlled trials were included in the meta-analysis. Results indicated that the clinical response rate at the test-of-cure visit with initial treatment of moxifloxacin was significantly higher than that of levofloxacin (3441 patients; random effects model; I² = 49%; odds ratio, 3.35; 95% CI, 2.35-4.77; P < 0.001). In terms of the safety profile, total adverse events were not significantly different between the 2 groups (2770 patients; random effects model; I² = 40%; odds ratio, 0.77; 95% CI, 0.56-1.06; P = 0.11). Output of the cost-utility model showed that under the willingness-to-pay threshold of one-time China gross domestic product per capita, moxifloxacin is dominant over levofloxacin, being less costly and more efficacious (0.002 quality-adjusted life year gained, CNY 844 [US$131] saved in total cost, negative incremental cost-effectiveness ratio). Sensitivity analyses indicated the robustness of the model as moxifloxacin remained dominant when model parameter values fluctuated.

IMPLICATIONS

Moxifloxacin is more efficacious than levofloxacin as the initial empirical treatment for CAP. In addition, treatment of CAP with moxifloxacin instead of levofloxacin is expected to be cost-saving from the perspective of payers in China. However, for the cost-utility analysis, in the absence of a national representative database on costs for hospitalization in China, inputs in the cost-utility model could be underestimated or overestimated due to estimating errors applied to both treatment arms. (Clin Ther. 2021;43:XXX-XXX) © 2021 Elsevier HS Journals, Inc.

Older but Not Wiser: the Age-Driven Changes in Neutrophil Responses during Pulmonary Infections

Elderly individuals are at increased risk of life-threatening pulmonary infections. Neutrophils are a key determinant of the disease course of pathogen-induced pneumonia. Optimal host defense balances initial robust pulmonary neutrophil responses to control pathogen numbers, ultimately followed by the resolution of inflammation to prevent pulmonary damage. Recent evidence suggests that phenotypic and functional heterogeneity in neutrophils impacts host resistance to pulmonary pathogens. Apart from their apparent role in innate immunity, neutrophils also orchestrate subsequent adaptive immune responses during infection. Thus, the outcome of pulmonary infections can be shaped by neutrophils. This review summarizes the age-driven impairment of neutrophil responses and the contribution of these cells to the susceptibility of the elderly to pneumonia. We describe how aging is accompanied by changes in neutrophil recruitment, resolution, and function. We discuss how systemic and local changes alter the neutrophil phenotype in aged hosts. We highlight the gap in knowledge of whether these changes in neutrophils also contribute to the decline in adaptive immunity seen with age. We further detail the factors that drive dysregulated neutrophil responses in the elderly and the pathways that may be targeted to rebalance neutrophil activity and boost host resistance to pulmonary infections.

Multi-Valent Protein Hybrid Pneumococcal Vaccines: A Strategy for the Next Generation of Vaccines

Streptococcus pneumoniae (Spn) is a bacterial pathogen known to colonize the upper respiratory tract and cause serious opportunistic diseases such as pneumonia, bacteremia, sepsis and meningitis. As a consequence, millions of attributable deaths occur annually, especially among infants, the elderly and immunocompromised individuals. Although current vaccines, composed of purified pneumococcal polysaccharide in free form or conjugated to a protein carrier, are widely used and have been demonstrated to be effective in target groups, Spn has continued to colonize and cause life-threatening disease in susceptible populations. This lack of broad protection highlights the necessity of improving upon the current "gold standard" pneumococcal vaccines to increase protection both by decreasing colonization and reducing the incidence of sterile-site infections. Over the past century, most of the pneumococcal proteins that play an essential role in colonization and pathogenesis have been identified and characterized. Some of these proteins have the potential to serve as antigens in a multi-valent protein vaccine that confers capsule independent protection. This review seeks to summarize the benefits and limitations of the currently employed vaccine strategies, describes how leading candidate proteins contribute to pneumococcal disease development, and discusses the potential of these proteins as protective antigens-including as a hybrid construct.

The trend of emergency department visits among the elderly in Thailand

Emergency department (ED) usage by older adults tends to be a major health issue due to increase in aging population and their health fragility. Currently, there is no study comparing ED data of older adults with those of younger population in Southeast Asia. The aim of this study was to explore the epidemiologic data of elderly who visited the ED from 2016 to 2018 and compare them with data from younger group. Data on ED visits from 2016 to 2018 were extracted from the electronic medical database. Descriptive statistics were used for analyzing the collected data and compared with the data of the age group of 15-59 years. A total of 27,871 elderly patients were found eligible and included. The mean age was 72.69 years (95% confidence interval 72.6-72.8). Patients aged 60-69 years have the highest ED visits rate (45.4%). From the total visits, 58.06% were discharged from ED, while 40.82% were admitted to hospital with 11.22% death rate after the admission. The most diagnosed condition was injury, poisoning, or other consequence from an external cause, with a head injury as the leading cause (20.74%). Compared with patients aged 15-59 years, elderly patients had a higher visit rate per 1000 population (21.99 vs. 30.91; P < 0.001), more admissions (15% vs. 40.8%; P < 0.001), and more re-visits within 7 days (1.81% vs. 4.07%; P < 0.001). These results showed that older adult patients tend to have higher ED visits rate, ED re-visits rate, and admissions rate compared to younger age groups.

Etiology and Outcomes of ARDS in the Elderly Population in an Intensive Care Unit in North India

Background

Whether age would impact the outcomes in subjects with acute respiratory distress syndrome (ARDS) remains unclear. Herein, we study the effect of age as a predictor of mortality in ARDS.

Materials and methods

We categorized consecutive subjects with ARDS as either ARDS_elderly (age >65 years) or ARDSnon_elderly (age ≤65 years) admitted to the respiratory intensive care unit (ICU) of a tertiary care hospital in North India between January 2007 and December 2019. We compared the baseline clinical and demographic characteristics, lung mechanics, and mortality between the two groups. We also analyzed the factors predicting ICU survival using multivariate logistic regression analysis.

Results

We included 625 patients (ARDS_elderly, 140 [22.4%] and ARDS_nonelderly, 485 [77.6%]) with a mean (standard deviation) age (56.3% males) of 40.6 (17.8) years. The ARDS_elderly were more likely (p = 0.0001) to have the presence of any comorbid illness compared to ARDS_nonelderly. The elderly subjects had significantly higher pulmonary ARDS than the younger group. The severity of ARDS was however, similarly distributed between the two study arms. There were 224 (35.8%) deaths, and the mortality was significantly higher (p = 0.012) in the ARDS_elderly than the to ARDS_nonelderly (ARDS_elderly vs ARDS_nonelderly, 45 vs 33.2%). On multivariate logistic regression analysis, the baseline sequential organ failure assessment scores, presence of pulmonary ARDS, and the development of new organ dysfunction were the independent predictors of mortality.

Conclusion

The outcomes in subjects with ARDS are dependent on the severity of illness at admission and the etiology of ARDS rather than the age alone.

How to cite this article

Sehgal IS, Agarwal R, Dhooria S, Prasad KT, Muthu V, Aggarwal AN. Etiology and Outcomes of ARDS in the Elderly Population in an Intensive Care Unit in North India. Indian J Crit Care Med 2021;25(6):648–654.

Management and Outcomes of Suspected Infectious and Inflammatory Lung Abnormalities Identified on Lung Cancer Screening CT

Background: Incidental findings are frequently encountered during lung cancer screening (LCS). Limited data describe the prevalence of suspected acute infectious and inflammatory lung processes on LCS and how they should be managed. Objective: To determine the prevalence, radiologic reporting and management, and outcome of suspected infectious and inflammatory lung processes identified incidentally during LCS, and to propose a management algorithm. Methods: This retrospective study included 6314 low dose CT (LDCT) examinations performed between June 2014 and April 2019 in 3800 patients as part of an established LCS program. Radiology reports were reviewed, and patients with potentially infectious or inflammatory lung abnormalities were identified and analyzed for descriptors of imaging findings, Lung-RADS designation, recommendations, and clinical outcomes. Based on the descriptors, outcomes and a >2% threshold risk of malignancy, a follow-up algorithm was developed to decrease additional imaging without affecting cancer detection. Results: A total of 331/3800 (8.7%) patients (178 men, 153 women; mean age: 66 ± 7 years) undergoing LCS had lung findings that were attributed to infection or inflammation. These abnormalities were reported as potentially significant findings using the "S" modifier in 149/331 (45.0%) and as the "dominant nodule" determining the Lung-RADS category in 96/331 (29.0%). Abnormalities were multiple or multifocal in 260/331 (78.5%). Common descriptors were ground-glass (155/331; 46.8%), tree-in-bud (56/331; 16.9%), consolidation (41/331; 12.4%), and clustered (67/331; 20.2%) opacities. A follow-up chest CT outside of screening was performed within 12 months or less in 264/331 (79.8%) and within 6 months or less in 286/331 (56.2%). A total of 260/331 (78.5%) opacities resolved on follow-up imaging. Two malignancies (2/331; 0.60%) were associated with these abnormalities, and both had consolidations. Theoretical adoption of a proposed management algorithm for suspected infectious and inflammatory findings reduced unnecessary follow-up imaging by 82.6% without missing a single malignancy. Conclusions: Presumed acute infectious or inflammatory lung abnormalities are frequently encountered in the setting of LCS. These opacities are commonly multifocal and resolve on follow-up. Less than 1% are associated with malignancy. Clinical impact: Adoption of a conservative management algorithm can standardize recommendations and reduce unnecessary imaging without increasing the risk of missing a malignancy.

Defensive Properties of Mucin Glycoproteins during Respiratory Infections-Relevance for SARS-CoV-2

Mucus plays a pivotal role in protecting the respiratory tract against microbial infections. It acts as a primary contact site to entrap microbes and facilitates their removal from the respiratory tract via the coordinated beating of motile cilia. The major components of airway mucus are heavily O-glycosylated mucin glycoproteins, divided into gel-forming mucins and transmembrane mucins. The gel-forming mucins MUC5AC and MUC5B are the primary structural components of airway mucus, and they enable efficient clearance of pathogens by mucociliary clearance. MUC5B is constitutively expressed in the healthy airway, whereas MUC5AC is upregulated in response to inflammatory challenge. MUC1, MUC4, and MUC16 are the three major transmembrane mucins of the respiratory tracts which prevent microbial invasion, can act as releasable decoy receptors, and activate intracellular signal transduction pathways. Pathogens have evolved virulence factors such as adhesins that facilitate interaction with specific mucins and mucin glycans, for example, terminal sialic acids. Mucin expression and glycosylation are dependent on the inflammatory state of the respiratory tract and are directly regulated by proinflammatory cytokines and microbial ligands. Gender and age also impact mucin glycosylation and expression through the female sex hormone estradiol and age-related downregulation of mucin production. Here, we discuss what is currently known about the role of respiratory mucins and their glycans during bacterial and viral infections of the airways and their relevance for the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Understanding the impact of microbe-mucin interaction in the respiratory tract could inspire the development of novel therapies to boost mucosal defense and combat respiratory infections.

From virus to inflammation, how influenza promotes lung damage

Despite seasonal vaccines, influenza-related hospitalization and death rates have remained unchanged over the past 5 years. Influenza pathogenesis has 2 crucial clinical components; first, influenza causes acute lung injury that may require hospitalization. Second, acute injury promotes secondary bacterial pneumonia, a leading cause of hospitalization and disease burden in the United States and globally. Therefore, developing an effective therapeutic regimen against influenza requires a comprehensive understanding of the damage-associated immune-mechanisms to identify therapeutic targets for interventions to mitigate inflammation/tissue-damage, improve antiviral immunity, and prevent influenza-associated secondary bacterial diseases. In this review, the pathogenic immune mechanisms implicated in acute lung injury and the possibility of using lung inflammation and barrier crosstalk for developing therapeutics against influenza are highlighted.

The Prevalence of Anticholinergic Drugs and Correlation with Pneumonia in Elderly Patients: A Population-Based Study in Taiwan

Anticholinergic drugs may increase the risk of serious respiratory infection, especially in the elderly. The study aims to investigate the prevalence of anticholinergic drugs and the correlation of incident pneumonia associated with the use of anticholinergic drugs among the elderly in Taiwan. The study population was 275,005 elderly patients aged ≥65 years old, selected from the longitudinal health insurance database (LHID) in 2016. Among all the elderly patients, about 60% had received anticholinergic medication at least once. Furthermore, the study selected elderly patients who had not been diagnosed with pneumonia and had not received any anticholinergic drugs in the past year in order to evaluate the correlation between pneumonia and anticholinergic drugs. The study excluded elderly patients who died or had received related drugs of incident pneumonia during the study period and selected elderly patients receiving anticholinergic drugs as the case group. Propensity score matching (PSM) on a 1:1 scale was used to match elderly patients that were not receiving any anticholinergic drugs as the control group, resulting in a final sample of 32,215 patients receiving anticholinergic drugs and 32,215 patients not receiving any anticholinergic drugs. Conditional logistic regression was used to estimate the association between anticholinergic drugs and pneumonia after controlling for potential confounders. Compared with patients not receiving anticholinergic drugs, the adjusted odds ratio of patients receiving anticholinergic drugs was 1.33 (95% confidence interval: 1.18 to 1.49). Anticholinergic medication is common among elderly patients in Taiwan. Elderly patients receiving anticholinergic drugs may increase their risk of incident pneumonia. The safety of anticholinergic drugs in the elderly should be of concern in Taiwan.

Comparison of antimicrobial resistance patterns in Streptococcus pneumoniae from respiratory and blood cultures in Canadian hospitals from 2007-16

OBJECTIVES

To compare the epidemiology and antimicrobial susceptibility patterns of Streptococcus pneumoniae collected from respiratory and blood culture samples in Canada between 2007 and 2016.

METHODS

S. pneumoniae strains were obtained from Canadian hospitals as part of the ongoing national surveillance study, CANWARD. Isolates were serotyped using the Quellung method. Antimicrobial susceptibility testing was performed using the CLSI broth microdilution method. MDR and XDR were defined as resistance to three or more and five or more classes of antimicrobials, respectively.

RESULTS

Of the 2581 S. pneumoniae isolates collected, 1685 (65.3%) and 896 (34.7%) were obtained from respiratory and blood samples, respectively. Respiratory isolates demonstrated lower rates of antimicrobial susceptibility than blood isolates to penicillin, ceftriaxone, clarithromycin, clindamycin, doxycycline and trimethoprim/sulfamethoxazole (P ≤ 0.03). From 2007 to 2016, invasive isolates demonstrated trends towards increasing penicillin susceptibility and decreasing clarithromycin susceptibility. MDR was significantly higher in respiratory S. pneumoniae compared with blood (9.1% versus 4.5%, P < 0.0001). Serotypes 11A, 16F, 19F, 23A/B/F, 34, 35B and non-typeable strains were more commonly isolated from respiratory specimens, while 4, 5, 7F, 8, 12F, 14 and 19A were more commonly invasive serotypes. Numerous serotypes, including 3 and 22F, were isolated frequently from both specimen sources.

CONCLUSIONS

S. pneumoniae from respiratory samples demonstrated lower antimicrobial susceptibilities and higher MDR in a greater diversity of serotypes than isolates obtained from blood. Many serotypes were associated with one specific specimen source, while others were associated with both; genetic characterization is necessary to elucidate the specific factors influencing the ability of these serotypes to commonly cause both invasive and non-invasive disease.

Routine infant vaccination of pneumococcal conjugate vaccines has decreased pneumonia across all age groups in Northern Spain

Since the early 2000s, pneumococcal conjugate vaccines (PCVs) have been shown to be effective in the prevention of pneumonia and invasive pneumococcal diseases. In 2011, the Galician region incorporated PCV in the routine infant immunization, the very first stable program in Spain. We aim to assess direct and indirect benefits of PCV vaccination on all-cause pneumonia in the region across different age groups using an ecological study design. For this, we calculated the annual hospitalization rates using a hospital-based disease registry. We identified all-cause pneumonia, pneumococcal pneumonia and pneumococcal invasive diseases within the registry. Hospitalization rates were computed and compared across three study periods: pre-vaccination (1998-2003), early-vaccination (2005-2009) and routine-vaccination (2011-2015). Across Northern Spain, we identified 114,873 all-cause pneumonia hospitalizations, of which 24,808 were further diagnosed with pneumococcal pneumonia. The majority were elderly > 64 years (67.3%). Hospitalizations from all-cause pneumonia had a net increase from 20.6 (pre-PCV) and 21.4/10,000 (early) to 28.4/10,000 (routine) (+32.7%, p < .0001), this is attributed to the huge number of cases in the elderly age group. In contrast, a net reduction of incidence of hospitalized pneumococcal pneumonia was observed from 6.3/10,000 (pre-PCV) and 5.7/10,000 (early) to 2.4/10,000 (routine) cases (-57.9%, p < .0001). Thus, routine infant vaccination may have resulted to an overall decline of pneumococcal pneumonia in infants, as well as in elderly age groups. However, a paradoxical increase on all-cause pneumonia was observed in Galicia, mostly attributed to the growing number of cases in the elderly population.

Vascular Niche in Lung Alveolar Development, Homeostasis, and Regeneration

Endothelial cells (ECs) constitute small capillary blood vessels and contribute to delivery of nutrients, oxygen and cellular components to the local tissues, as well as to removal of carbon dioxide and waste products from the tissues. Besides these fundamental functions, accumulating evidence indicates that capillary ECs form the vascular niche. In the vascular niche, ECs reciprocally crosstalk with resident cells such as epithelial cells, mesenchymal cells, and immune cells to regulate development, homeostasis, and regeneration in various organs. Capillary ECs supply paracrine factors, called angiocrine factors, to the adjacent cells in the niche and orchestrate these processes. Although the vascular niche is anatomically and functionally well-characterized in several organs such as bone marrow and neurons, the effects of endothelial signals on other resident cells and anatomy of the vascular niche in the lung have not been well-explored. This review discusses the role of alveolar capillary ECs in the vascular niche during development, homeostasis and regeneration.

Adverse Events Associated with Cumulative Corticosteroid Use in Patients with Castration-Resistant Prostate Cancer: An Administrative Claims Analysis

INTRODUCTION

Corticosteroids are a mainstay treatment for castration-resistant prostate cancer (CRPC). Although corticosteroids have been associated with adverse events, long-term outcomes related to their sustained use have not been assessed in men with CRPC.

OBJECTIVE

This study evaluated the impact of cumulative corticosteroid exposure on the risk of developing specific adverse events in men with CRPC.

METHODS

Data were obtained from administrative claims databases. Adult chemotherapy-naïve men who initiated CRPC treatment following surgical or medical castration were selected. Patients were grouped into four cohorts based on cumulative corticosteroid dose: no exposure, low exposure (< 0.5 g), medium exposure (0.5-2.0 g), and high exposure (> 2.0 g). Time to each adverse event was assessed using Kaplan-Meier analyses and time-dependent Cox proportional hazard models, adjusting for baseline characteristics.

RESULTS

Overall, 9425 patients were included (no exposure, N = 6765; low exposure, N = 1660; medium exposure, N = 655; high exposure, N = 345). The mean age was 71-76 years across cohorts. During the study period, cumulative corticosteroid exposure was associated with a significantly higher risk of developing an infection [high vs. no exposure, adjusted hazard ratio (HR) 2.55; 95% confidence interval (CI) 2.27-2.85; p < 0.001 for trend], peptic ulcer (HR 1.91; 95% CI 1.39-2.64; p < 0.001), acute cardiovascular events (HR 1.62; 95% CI 1.43-1.83; p < 0.001), endocrine disorder (HR 1.61; 95% CI 1.34-1.94; p < 0.001), fracture (HR 1.59; 95% CI 1.37-1.86; p < 0.001), or mental health condition (HR 1.28; 95% CI 1.06-1.55; p = 0.014). Exposure to corticosteroids was associated with a more rapid onset of adverse events.

CONCLUSION

Patients with CRPC receiving corticosteroids had a higher risk of developing a wide range of adverse events than those not receiving them. The increased adverse event risk was observed after accounting, to the extent possible, for patients' overall disease severity.

Prognostic significance of malnutrition for long-term mortality in community-acquired pneumonia: a propensity score matched analysis

BACKGROUND/AIMS

The impact of malnutrition on the outcome of hospitalized adults with community-acquired pneumonia (CAP) has not been fully investigated. This study evaluated the prevalence and prognostic significance of malnutrition in a Korean population with CAP.

METHODS

In total, 198 patients with CAP from November 2014 to September 2015 were analyzed retrospectively. We assessed the prevalence of malnutrition and the risk factors for 2-year mortality. Furthermore, we divided the patients into two groups: elderly (age ≥ 65 years, n = 131) and non-elderly (age < 65 years, n = 67). Subgroup analyses were performed in the elderly group through propensity score matching.

RESULTS

The prevalence of malnutrition was 39.4%, and the proportion of patients with malnutrition was significantly higher (53.4% vs. 11.9%, p < 0.001) in the elderly group than in the non-elderly group. In-hospital mortality, 1-year mortality, and 2-year mortality rates were 4.5%, 19.2%, and 26.8%, respectively. Multivariate Cox regression analyses revealed that malnutrition (odds ratio [OR], 2.52; 95% confidence interval [CI], 1.39 to 4.60; p = 0.002) and the Charlson comorbidity index score (OR, 1.30; 95% CI, 1.17 to 1.45; p < 0.001) were associated with 2-year mortality.

CONCLUSION

Malnutrition was common and associated with a poor long-term outcome in patients with CAP, particularly the elderly. A routine nutritional assessment at admission is mandatory as a first step for appropriate nutritional therapy.

Summary of the 2018 Alcohol and Immunology Research Interest Group (AIRIG) meeting

On January 26, 2018, the 23rd annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held at the University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado. The meeting consisted of plenary sessions with oral presentations and a poster presentation session. There were four plenary sessions that covered a wide range of topics relating to alcohol use: Alcohol and Liver Disease; Alcohol, Inflammation and Immune Response; Alcohol and Organ Injury; Heath Consequences and Alcohol Drinking. The meeting provided a forum for the presentation and discussion of novel research findings regarding alcohol use and immunology.

Alterations of the respiratory system in heart failure

The review discusses mechanisms for the development of the pathology of the respiratory system in patients with CHF, such as various types of periodic respiration, pulmonary hypertension due to the pathology of the left chambers of the heart, and remodeling of the respiratory musculature. The role of chemo- and baroreceptors of the carotid zone, as well as the hyperactivation of the respiratory muscle metaboreflex in the development of the pathology of the respiratory system, and the mediated exacerbation of CHF are discussed.

Early improvement in severely ill patients with pneumonia treated with ceftobiprole: a retrospective analysis of two major trials

BACKGROUND

Patients with pneumonia who are elderly or severely ill are at a particularly high risk of mortality. This post hoc retrospective analysis of data from two Phase III studies evaluated early improvement outcomes in subgroups of high-risk patients with community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP, excluding ventilator-associated pneumonia [VAP]).

METHODS

One study included hospitalised CAP patients randomised to ceftobiprole or ceftriaxone ± linezolid treatment. The other study included HAP patients, who were randomised to ceftobiprole or ceftazidime plus linezolid treatment. The primary outcome was rate of early clinical response (Day 3 in CAP and Day 4 in HAP patients). Additional outcome measures included clinical cure at a test-of-cure visit, 30-day all-cause mortality and safety.

RESULTS

The overall high-risk group comprised 398 CAP patients and 307 HAP patients with risk factors present at baseline. The rate of early response was numerically higher in ceftobiprole-treated patients vs comparator-treated patients in the following high-risk groups: CAP patients aged ≥75 years (16.3% difference, 95% confidence interval [CI]: 1.8, 30.8); CAP patients with COPD (20.1% difference, 95% CI: 8.8, 31.1); all high-risk HAP patients (12.5% difference, 95% CI: 3.5, 21.4); HAP patients with >10 baseline comorbidities (15.3% difference, 95% CI: 0.3, 30.4).

CONCLUSIONS

Previous studies show that ceftobiprole is an efficacious therapy for patients with pneumonia who are at high risk of poor outcomes. This post hoc analysis provides preliminary evidence that ceftobiprole treatment may have advantages over other antibiotics in terms of achieving early improvement in high-risk patients with HAP (excluding VAP) and in some subgroups of high-risk CAP patients.

TRIAL REGISTRATION

NCT00210964 : registered September 21, 2005; NCT00229008 : registered September 29, 2005; NCT00326287 : registered May 16, 2006.

Pneumonia hospitalisation and case-fatality rates in older Australians with and without risk factors for pneumococcal disease: implications for vaccine policy

Community-acquired pneumonia (CAP) results in substantial numbers of hospitalisations and deaths in older adults. There are known lifestyle and medical risk factors for pneumococcal disease but the magnitude of the additional risk is not well quantified in Australia. We used a large population-based prospective cohort study of older adults in the state of New South Wales (45 and Up Study) linked to cause-specific hospitalisations, disease notifications and death registrations from 2006 to 2015. We estimated the age-specific incidence of CAP hospitalisation (ICD-10 J12-18), invasive pneumococcal disease (IPD) notification and presumptive non-invasive pneumococcal CAP hospitalisation (J13 + J18.1, excluding IPD), comparing those with at least one risk factor to those with no risk factors. The hospitalised case-fatality rate (CFR) included deaths in a 30-day window after hospitalisation. Among 266 951 participants followed for 1 850 000 person-years there were 8747 first hospitalisations for CAP, 157 IPD notifications and 305 non-invasive pneumococcal CAP hospitalisations. In persons 65-84 years, 54.7% had at least one identified risk factor, increasing to 57.0% in those ⩾85 years. The incidence of CAP hospitalisation in those ⩾65 years with at least one risk factor was twofold higher than in those without risk factors, 1091/100 000 (95% confidence interval (CI) 1060-1122) compared with 522/100 000 (95% CI 501-545) and IPD in equivalent groups was almost threefold higher (18.40/100 000 (95% CI 14.61-22.87) vs. 6.82/100 000 (95% CI 4.56-9.79)). The CFR increased with age but there were limited difference by risk status, except in those aged 45 to 64 years. Adults ⩾65 years with at least one risk factor have much higher rates of CAP and IPD suggesting that additional risk factor-based vaccination strategies may be cost-effective.

The burden of community-acquired bacterial pneumonia in the era of antibiotic resistance

INTRODUCTION

Community-acquired pneumonia (CAP) is a significant global health problem and leading cause of death and hospitalization in both the US and abroad. Increasing macrolide resistance among Streptococcus pneumoniae and other pathogens results in a greater disease burden, along with changing demographics and a higher preponderance of comorbid conditions. Areas covered: This review summarizes current data on the clinical and economic burden of CAP, with particular focus on community-acquired bacterial pneumonia (CABP). Incidence, morbidity and mortality, and healthcare costs for the US and other regions of the world are among the topics covered. Major factors that are believed to be contributing to the increased impact of CABP, including antimicrobial resistance, the aging population, and the incidence of comorbidities are discussed, as well as unmet needs in current CABP management. Expert commentary: The clinical and economic burden of CABP is staggering, far-reaching, and expected to increase in the future as new antibiotic resistance mechanisms emerge and the world's population ages. Important measures must be initiated to stabilize and potentially decrease this burden. Urgent needs in CABP management include the development of new antimicrobials, adjuvant therapies, and rapid diagnostics.

Perceptions of Seasonal Influenza and Pneumococcal Vaccines Among Older Chinese Adults

BACKGROUND AND OBJECTIVES

Seasonal influenza can lead to pneumonia. In Hong Kong, deaths from pneumonia increased steadily from 2001 to 2015, and pneumonia was the second most common cause of death between 2012 and 2015. The seasonal influenza vaccine and pneumococcal vaccine have been clinically proven as effective measures against these two diseases among older adults, who are at particularly high risk. Despite the availability of vaccine subsidies, however, more than 60% of older adults in Hong Kong remain unvaccinated against pneumococcal diseases and seasonal influenza. The objective of this study was to investigate the perceptions and barriers associated with the seasonal influenza and pneumococcal vaccinations among older adults in Hong Kong.

RESEARCH DESIGN AND METHODS

A qualitative approach of individual semistructured interviews was adopted; 40 adults aged 65 years and older were interviewed between September and November 2016.

RESULTS

The intersecting influences of belief of vaccines as harmful, low perceived risk of contracting the diseases, negative rumors about the vaccines, lack of promotion by health care providers, the perceived risk posed by the vaccinating locations, and the preference of using traditional Chinese medicine were discovered to prevent the participants from receiving the two vaccinations.

DISCUSSION AND IMPLICATIONS

Perceptions and cultural factors should be considered in future vaccination promotion among older adults. This study found that, in particular, the participants' cultural associations and stereotypes of hospitals and clinics and health care providers' lack of perceived need to vaccinate older adults contributed to low vaccine acceptance among the participants.

Age-related changes in the levels and kinetics of pulmonary cytokine and chemokine responses to Streptococcuspneumoniae in mouse pneumonia models

Streptococcuspneumoniae is a major human pathogen at the extremes of age. The elderly are particularly vulnerable to S.pneumoniae, the most common causative agent of bacterial pneumonia in this population. Despite the availability of vaccines and antibiotics, mortality rates associated with pneumococcal pneumonia in this age group remain high. In light of globally increasing life-expectancy, a better understanding of the patho-mechanisms of elderly pneumococcal pneumonia, including alterations in innate immune responses, is needed to develop improved therapies. In this study we aimed at investigating how increased susceptibility to pneumococcal infection relates to inflammation kinetics in the aged mouse pneumonia model by determining pulmonary cytokine and chemokine levels and comparing these parameters to those measured in young adult mice. Firstly, we detected overall higher pulmonary cytokine and chemokine levels in aged mice. However, upon induction of pneumococcal pneumonia in aged mice, delayed production of certain analytes, such as IFN-γ, MIG (CXCL9), IP-10 (CXCL10), MCP-1 (CCL2), TARC (CCL17) and MDC (CCL22) became apparent. In addition, aged mice were unable to control excess inflammatory responses: while young mice showed peak inflammatory responses at 20 h and subsequent resolution by 48 h post intranasal challenge, in aged mice increasing cytokine and chemokine levels were measured. These findings highlight the importance of considering multiple time points when delineating inflammatory responses to S.pneumoniae in an age-related context. Finally, correlation between pulmonary bacterial burden and cytokine or chemokine levels in young mice suggested that appropriately controlled inflammatory responses support the host to fight pneumococcal infection.

Are Early Warning Scores Useful Predictors for Mortality and Morbidity in Hospitalised Acutely Unwell Older Patients? A Systematic Review

BACKGROUND

Early warning scores (EWSs) are used to identify deteriorating patients for appropriate interventions. We performed a systematic review to examine the usefulness of EWSs in predicting inpatient mortality and morbidity (transfer to higher-level care and length of hospital stay) in older people admitted to acute medical units with sepsis, acute cardiovascular events, or pneumonia.

METHODS

A systematic review of published and unpublished databases was conducted. Cochrane's tool for assessing Risk of Bias in Non-Randomised Studies-of Interventions (ROBINS-I) was used to appraise the evidence. A narrative synthesis was performed due to substantial heterogeneity.

RESULTS

Five studies (n = 12,057) were eligible from 1033 citations. There was an overall "moderate" risk of bias for all studies. The predictive ability of EWSs regarding mortality was reported in one study (n = 274), suggesting EWSs were better at predicting survival, (negative predictive value >90% for all scores). Three studies (n = 1819) demonstrated a significant association between increasing modified EWSs (MEWSs) and increased risk of mortality. Hazards ratios for a composite death/intensive care (ICU) admission with MEWSs ≥5 were significant in one study (p = 0.003). Two studies (n = 1421) demonstrated that a MEWS ≥6 was associated with 21 times higher probability of mortality (95% Confidence Interval (CI): 2.71⁻170.57) compared with a MEWS ≤1. A MEWS of ≥5 was associated with 22 times higher probability of mortality (95% CI: 10.45⁻49.16).

CONCLUSION

Increasing EWSs are strongly associated with mortality and ICU admission in older acutely unwell patients. Future research should be targeted at better understanding the usefulness of high and increasing EWSs for specific acute illnesses in older adults.

Relative Clinical and Cost Burden of Community-Acquired Pneumonia Hospitalizations in Older Adults in the United States-A Cross-Sectional Analysis

The relative burden of community-acquired pneumonia (CAP) in older adults (≥65 years old) compared to other serious diseases is important to prioritize preventive treatment. A retrospective analysis was conducted using the 2014 National Readmission Database to evaluate the length of stay, inpatient mortality, 30-day readmissions, and costs of CAP compared to diabetes mellitus (DM), myocardial infarction (MI), and stroke. 275,790 hospitalizations were analyzed and represented a national estimate of 616,300 hospitalizations, including 269,961 for CAP, 71,284 for DM, 126,946 for MI, and 148,109 for stroke. The mean length of stay in CAP was 5.2 days, which was higher than DM (4.6) and MI (4.3) but similar to stroke (5.6). The inpatient mortality risk was lower for DM (RR: 0.37, 95% CI: 0.29–0.46) but higher for MI (RR: 1.67, 95% CI: 1.50–1.85) and stroke (RR: 1.67, 95% CI: 1.51–1.83). The median costs for CAP ($7282) were higher compared to DM ($6217) but lower compared to MI ($14,802) and stroke ($8772). The 30-day readmission rate was 17% in CAP, which was higher compared to MI (15%) and stroke (11.5%) and lower compared to DM (20.3%). In patients with CAP, disease burden is on par with other serious diseases. CAP should be prioritized for prevention in older adults with strategies such as vaccination and smoking cessation.

Streptococcus pneumoniae's Virulence and Host Immunity: Aging, Diagnostics, and Prevention

Streptococcus pneumoniae is an infectious pathogen responsible for millions of deaths worldwide. Diseases caused by this bacterium are classified as pneumococcal diseases. This pathogen colonizes the nasopharynx of its host asymptomatically, but overtime can migrate to sterile tissues and organs and cause infections. Pneumonia is currently the most common pneumococcal disease. Pneumococcal pneumonia is a global health concern and vastly affects children under the age of five as well as the elderly and individuals with pre-existing health conditions. S. pneumoniae has a large selection of virulence factors that promote adherence, invasion of host tissues, and allows it to escape host immune defenses. A clear understanding of S. pneumoniae's virulence factors, host immune responses, and examining the current techniques available for diagnosis, treatment, and disease prevention will allow for better regulation of the pathogen and its diseases. In terms of disease prevention, other considerations must include the effects of age on responses to vaccines and vaccine efficacy. Ongoing work aims to improve on current vaccination paradigms by including the use of serotype-independent vaccines, such as protein and whole cell vaccines. Extending our knowledge of the biology of, and associated host immune response to S. pneumoniae is paramount for our improvement of pneumococcal disease diagnosis, treatment, and improvement of patient outlook.

Costs associated with community acquired pneumonia in France

OBJECTIVES

Pneumocost is a prospective study that aimed at documenting the costs of the management of patients hospitalized with a pneumococcal pneumonia and the post-discharge costs during a 6-month period in the French context.

METHODS

Billing data were used to document hospital costs. Resource use during the follow-up period was collected through phone interviews at month 1, 3 and 6. Descriptive statistics and multivariate analyses were performed. We used generalized linear models with log-link functions to estimate parameters associated with hospital and follow-up costs of patients.

RESULTS

Five hundred twenty-four patients were enrolled in 40 public centers from October 2011 to April 2014. Average age was 63 (SD 17); 55.0% of them were male. Average length of stay was 15 days (SD 23). Average cost of stay for the French Sickness Fund was €7293 (SD €7363). Average cost of follow-up was €1242 (SD €3000) and decreased steadily through time. When controlling for patient's socioeconomic characteristics, severity of disease and hospital stay, results showed a concave relationship between hospital costs and age. Obesity, the severity of the disease and comorbidities were associated with constantly increasing inpatient costs. Concerning follow-up costs, we found the same concave relationship with age, while gender, a history of pneumonia and severity of the disease were the most important predictors of high costs after discharge.

CONCLUSION

Pneumocost is the first French study providing a robust estimation of the cost of managing invasive pneumococcal pneumonia in the French context.

Development of a Risk Tool to Support Discussions of Care for Older Adults Admitted to the ICU With Pneumonia

BACKGROUND

Early, data-driven discussion surrounding palliative care can improve care delivery and patient experience.

OBJECTIVE

To develop a 30-day mortality prediction tool for older patients in intensive care unit (ICU) with pneumonia that will initiate palliative care earlier in hospital course.

DESIGN

Retrospective Electronic Health Record (EHR) review.

SETTING

Four urban and suburban hospitals in a Western New York hospital system.

PARTICIPANTS

A total of 1237 consecutive patients (>75 years) admitted to the ICU with pneumonia from July 2011 to December 2014.

MEASUREMENTS

Data abstracted included demographics, insurance type, comorbidities, and clinical factors. Thirty-day mortality was also determined. Logistic regression identified predictors of 30-day mortality. Area under the receiver operating curve (ROC) was calculated to quantify the degree to which the model accurately classified participants. Using the coordinates of the ROC, a predicted probability was identified to indicate high risk.

RESULTS

A total of 1237 patients were included with 30-day mortality data available for 100% of patients. The mortality rate equaled 14.3%. Age >85 years, having active cancer, Congestive Heart Failure (CHF), Chronic Obstructive Pulmonary Disease (COPD), sepsis, and being on a vasopressor all predicted mortality. Using the derived index, with a predicted probability of mortality >0.146 as a cutoff, sensitivity equaled 70.6% and specificity equaled 65.6%. The area under the ROC was 0.735.

CONCLUSION

Our risk tool can help care teams make more informed decisions among care options by identifying a patient group for whom a careful review of goals of care is indicated both during and after hospitalization. External validation and further refinement of the index with a larger sample will improve prognostic value.

RSV Infection in Human Macrophages Promotes CXCL10/IP-10 Expression during Bacterial Co-Infection

Respiratory syncytial virus (RSV), a major etiologic agent of acute lower respiratory infection constitutes the most important cause of death in young children worldwide. Viral/bacterial mixed infections are related to severity of respiratory inflammatory diseases, but the underlying mechanisms remain poorly understood. We have previously investigated the intracellular mechanisms that mediate the immune response in the context of influenza virus/Streptococcus pneumoniae (Sp) co-infection using a model of human monocyte-derived macrophages (MDMs). Here, we set up and characterized a similar model of MDMs to investigate different scenarios of RSV infection and co-infection with Sp. Our results suggest that Sp contributes to a faster and possibly higher level of CXCL10/IP-10 expression induced by RSV infection in human MDMs.

Diagnosis and treatment of community-acquired pneumonia in adults: 2016 clinical practice guidelines by the Chinese Thoracic Society, Chinese Medical Association

Community‐acquired pneumonia (CAP) in adults is an infectious disease with high morbidity in China and the rest of the world. With the changing pattern in the etiological profile of CAP and advances in medical techniques in diagnosis and treatment over time, Chinese Thoracic Society of Chinese Medical Association updated its CAP guideline in 2016 to address the standard management of CAP in Chinese adults. Extensive and comprehensive literature search was made to collect the data and evidence for experts to review and evaluate the level of evidence. Corresponding recommendations are provided appropriately based on the level of evidence. This updated guideline covers comprehensive topics on CAP, including aetiology, antimicrobial resistance profile, diagnosis, empirical and targeted treatments, adjunctive and supportive therapies, as well as prophylaxis. The recommendations may help clinicians manage CAP patients more effectively and efficiently. CAP in pediatric patients and immunocompromised adults is beyond the scope of this guideline. This guideline is only applicable for the immunocompetent CAP patients aged 18 years and older. The recommendations on selection of antimicrobial agents and the dosing regimens are not mandatory. The clinicians are recommended to prescribe and adjust antimicrobial therapies primarily based on their local etiological profile and results of susceptibility testing, with reference to this guideline.